Method of making a neutral wire connector



1965 H. l. STANBACK ETAL 3,228,094

METHOD OF MAKING A NEUTRAL WIRE CONNECTOR FilGd 001;. 21, 1964 34 jar/ &5 I 514mm diff 6a! f/zzellefl INVENTORS United States Patent 3,228,094 METHOD OF MAKING A NEUTRAL WIRE CONNECTOR Harris I. Stanback and Alfred Mueller, Lexington, Ky.,

assignors to Square D Company, Park Ridge, 111., a

corporation of Michigan Filed Oct. 21, 1964, Ser. No. 406,670 1 Claim. (Cl. 29155.55)

This is a continuation-in-part of copending application, Serial No. 168,733, filed January 25, 1962, now abandoned.

This invention relates generally to connector means, and more particularly to an improved method of making an electrical connector for electrically connecting a plurality of electrical conductors to a common potential. The connector means is thus suitable for use as a neutral wire connector or so-called neutral bar.

Prior to this invention, neutral wire connectors were made by a variety of considerably more expensive methods. One of the prior methods comprised providing a solid bar, drilling a first set of holes in the bar for receiving wires to be clamped, and drilling a second set of holes in the bar for receiving clamping screws, the holes of the second set respectively intersecting the holes of the first set.

Another of the prior methods comprised providing a flat sheet, punching at least three rows of holes in the fiat sheet, and forming the punched flat sheet into a generally rectangular tubular shape to dispose the outer two rows of holes in opposite side wall portions of the formed tube for receiving wires and to dispose the center row of holes in a third wall portion of the formed tube for receiving clamping screws.

These two prior methods thus teach that when the raw stock is a solid bar, the holes for the wires and clamping screws should be formed in the solid bar by drilling, and that when a process of punching holes in solid material is used, the raw stock should be a flat sheet which is formed into a tubular shape after the holes are punched therein. This invention departs from these teachings of the prior art.

An important object of the invention is to provide an improved method of making a connector means which may be used as a neutral wire connector and which is relatively easy and economical to manufacture.

A further object is to provide an improved method of making a neutral wire connector which is light, strong, rigid, and compact, and which can accommodate a relatively large number of wires per unit of length.

Another object is to provide an improved method of making a universal neutral wire connector adapted to receive a relatively large number of different sizes of wire and adapted to be cut from long stock lengths into suitable different shorter lengths for installation in different sizes of enclosed electrical panelboards accommodating different numbers of wires.

Other objects and advantages will appear upon consideration of the following description and accompanying drawings wherein:

FIG. 1 is a perspective view of a portion of a body member of a connector constructed in accordance with the invention;

FIG. 2 is a longitudinal sectional view of the connector in elevation taken in the direction of arrows 22 of FIG. 1 and showing some typical clamping screws and conductors clamped thereby;

FIG. 3 is a plan view of the connector of FIG. 2; and

FIG. 4 is a cross sectional view taken along lines 4-4 of FIG. 2.

In the drawings, a neutral wire connector constructed in accordance with the invention includes a bar 3,2Z8fl9d Patented Jan. 11, 1966 or body member 12 and a plurality of screws 14 adapted to clamp wires of various sizes such as a pair of illustrated wires 16 and 18.

The body member 12 may be of aluminum, copper, or other suitable electrically conductive material, and in accordance with the invention, it is made from a solid bar generally rectangular in cross section with unequal cross sectional dimensions in directions parallel respectively to pairs of opposite side surfaces of the bar and adapted to be economically formed by an extrusion process. A plurality of relatively closely spaced wirereceiving holes 20 and 21 of predetermined size are first formed in the solid bar 12 by a punching process and extend completely through the bar 12 from one surface thereof to the opposite surface in the direction of the short cross sectional dimension. The holes 20 and 21 are closely spaced so that a relatively large number of wires may be accommodated per unit of length of the bar 12. The predetermined thickness of material remaining between the holes 20 and 21 is considerably less than the width of the holes themselves and may actually be less than half the width of the holes. The holes 20 and 21 are alternately spaced, the holes 20 being larger and generally circular, and the holes 21 being slightly smaller and generally oblong. The smaller width of the holes 21 further increases the number of holes that can be punched in a given length of the bar 12, and the holes 20 and 21 respectively accommodate two different maximum sizes of wires.

A plurality of holes 22 extending in the direction of the long cross sectional dimension of the bar 12 and smaller than the predetermined size of the holes 20 and 21 is then formed in the originally solid bar 12 also by a punching process, and the slugs formed during the punching of the holes 22 are removed respectively through the holes 20 and 21. The holes 22 may be threaded to accommodate the screws 14. The thickness of material remaining between the holes 22 is greater than the predetermined thickness of material remaining between the holes 20 and 21. The holes 22 respectively intersect the holes 20 and 21 at right angles and extend from a third surface of the bar 12 to the holes 20 and 21 rather than extending all the way through the bar 12 as the holes 20 and 21 do. If desired, however, one or two of the holes 22 in the bar 12 may be made to extend all the way through the bar to accommodate fastening screws (not shown) for securing the bar 12 in place on a piece of insulating material (not shown), the respective cross holes 20 or 21 for the one or two holes 22 having bar fastening screws therein not then being able to accommodate a wire.

The holes 20 and 21 are adapted to receive relatively large wires such as the wire 18, and means are provided for preventing excessive deformation of relatively small wires such as the wire 16. Thus, the holes 20 and 21 are respectively shaped to provide a plurality of small groove portions 24 in the bar 12, the grooves 24 being opposite the screw-receiving holes 22 and being adapted to partially receive the relatively small wires such as the wire 16, excessive deformation of which is prevented by engagement of the clamping screws 14 with the shoulders defining the groove portions 24.

It will be seen that an improved method of making a neutral wire connector has been provided which includes providing a solid bar generally rectangular in cross section and punching wire-receiving and clamping screw-receiving holes therein at relatively closely spaced intervals, the simple rectangular solid cross section being adapted to economical extrusion of the bar and the punching of the holes being a relatively inexpensive process. Further, the bar of the connector is strong and rigid in spite of the closely spaced holes, and the close spacing of the holes and the alternate spacing of the difierent sized holes result in ability to accommodate a relatively large number of wires per unit of length of the bar.

The invention is claimed as follows:

A method of making a neutral wire connector, said method comprising:

(a) providing an elongated generally rectangular elecsecond plurality of holes than said predetermined thickness,

(d) removing the slugs formed by the punching of said second plurality of holes from said bar respectively trically conductive solid bar having relatively long and short cross sectional dimensions defining the rela tive spacing respectively between two pairs of opposite side surfaces of said bar,

(b) punching a first plurality of holes of predetermined size completely through said bar in the direction of said short cross sectional dimension and in spaced relationship longitudinally of said bar leaving a predetermined thickness of material between adjacent holes of said first plurality of holes,

() punching a second plurality of holes smaller than said predetermined size partially through said bar in the direction of said long cross sectional dimension into axially intersecting relationship respectively with said first plurality of holes and in spaced relationship longitudinally of said bar leaving a greater thickness of material between adjacent holes of said 5 through said first plurality of holes, and

(e) threading a plurality of clamping screws respectively into said second plurality of holes.

References Cited by the Examiner UNITED STATES PATENTS 37,189 12/1862 Westlake 29-545 267,629 11/1882 Wilson 29--558 1,943,660 1/1934 Edwards 339--272 X 2,164,616 7/1939 Manny 29557 X 15 2,279,211 4/1942 Thomas 83519 2,358,745 9/ 1944 Stieglitz 29155.55 2,419,862 4/1957 Wales 29163.5 X 2,875,829 3/1959 Patrick 83-519 2,943,294 6/1960 Norden 339-198 X 2,984,818 6/1961 Logan 339-272 2,991,551 11/1961 Fogle et a1 29-545 3,001,172 9/ 1961 Cornell 339272 X WHITMORE A. WILTZ, Primary Examiner. JOHN F. CAMPBELL, Examiner. 

